Glass-drawing apparatus.



W.YL. CLAUSE & R. S. PEASE.

GLASS DRAWING APPARATUS.

APPLICATION FlLiD JAN23.1914.

Patented Oct.. 3,1916.

UMTED sauras earnur oFFIoE.

WILLIAM L. CLAUSE AND ROGER S. PEASE, OF PITTSBURGH, PENNSYLVANIA, ASSIGN- ORS TO PITTSBURGH PLATE GLASS COMPANY. OF PITTSBURGH, PENNSYLVANIA,

A CORPORATION OF PENNSYLVANIA.

GLASS-DRAWING APPARATUS.

Application filed January 23, 1914.

To all 1li/0m it may con@ rn Be it known thaty we, llViLLLvu L. @Luise and ROGER S. Pmsn, both citizens of the United States, and both residing al Pittsburgh, in the count-y of \llegheny and State of Pennsylvania, have invented certain new and useful Improvements in Glass-Drawing Apparatus, of which the following is a speciiication.

The invention relates to the art of glass drawing, and particularly to the, drawing of glass cylinders for the making of window glass. The invention has for its objects. the provision of a simplified apparatus for securing a more rapid drawing operation with the elimination of the major portion of the delay incident to the coolingr and reheating ordinarily occurring in connection with the operation of drawing direc-t from a tank.

The apparatus preferably employed is illustrated in the accompanying drawings, whe rein- Figure Lis a partial .section through a glass drawingr tank embodying our invention, with the parts in one position of use. Fig. 2 is a section similar to thatof Fig. l. but with the parts in another position, Vig. 3 is a partial horimntal section taken through the tank above the drawing extern sion. and Fig. 4 is a vertical section taken on the line Ill-IV of Fig. 2.

Referring to the drawings, l is the glass melting tank which may be of any approved form and which is provided with a rootless drawing extension or tank 2. This drawing extension has its side walls 3 of less height than is customary in drawing` extensions, so that the top surface 4 thereof lies just above the surface 5 or" the glass.

Mounted `emovably upon the top of the ,extension 2 is a cover 6 provided with depending Walls 7 upon three of its sides, the fourth side which comes next to the melting tank being open as indicated at 8 and regis teringr with a passageway 9 lying above the surface of the glass. A vertically movable gate l() operated from the cable l1. or any other suitable means, serves to close the passageway 9 when the cover is removed and the drawing operation is in progress, as in dicated in Fig. 2.

Floating partially submerged in the. glass are the drawing shells or rings 12 and 13.

Specification of Letters Patent.

atented (tot. 3, 1916.

serial No. 813,883. I

These drawing shells may be ot various designs, and it will be, understood that the invention is not limited to use with the particular style ot container or shell illustrated. They are preferably made circular in cross section, and preferably arranged so that the body of glass contained therein is in free eonununication with the body of glass in which they float. so that as the glass is drawn from a ring a fresh Supply flows :in from beneath., The rings or shells are designed to bring a fresh supply of hot glass from the melting tank to position for drawinf:r in theI extension 2, and after the drawing operation. tov carry the cold glass and the residue of the cylinder back into the melting tank. y

Starting with the parts inthe position illust rated in Fig. l, the operation is as follows: The cover (i is-tirst removed and the ring 1; drawn over to the position indicated in Fig. and the'gate 10 is lowered as indicated iu Fig. 2. After the glass in the. ring` 1i) has cooled sufficiently-due to its exposure to the atmosphere-the usual bait is inserted in the glass and the drawing operation conducted in the usual way, the cylinder 14 being illustrated in the Process of forma tion as indicated in Fig'. Q. After the cylv inder has been drawn to the proper length it is severed at the `bottom either by a torch or blow pipe, or by raising the gate 10 and permitting the heat from the passageway 9 to melt olf the bottom of they cylinder. after which the cylinder is removed and laken down in the usual way. The gate l0 is then raised.. the ring l' is pushed back into the melting tank. and the cover t positioned as indicated in Fig. l. This operation places the chamber formed upon the lower side ot the cover 6 in communication with the hot gases iu the. melting tank 1, and the glass in the extension Q is brought up `to the temperature of the glass in the uu-ltin'g tank. Another drawing ring l5 can then be brought into position in the extension and the operation repeated as above described. The manipulation of the rings as above. described is advantageous, as the` coldglass left in a ring after the drawing operation, and the residue of the cylinder, is gotten back into the melting tank and refined by exposure to a very high temper'zture, while the fresh ring which is brought into position 'contains fresh glass which has been very y procedure in so far as the manipulation of the ring is concerned is substantially the same as that heretofore described, the ring being drawn into position in the drawing extension, and after the draw being pushed back into the melting tank and another ring from the melting tank floated into position for a draw. When this procedure is practised the cover would be used only wien the apparatus is shut down for a considerable period, or at infrequent periods to secure the heating up of the glass in the extension 2 when such glass becomes unduly cool due to the continued exposure of the surface. l

Our invention is designed primarily to do away with the necessity of usingr the socalled top stone hitherto used in drawing directly from a tank, and to decrease the interval between draws, thus increasing the capacity of the furnace employed. Where a perforate cover or Atop stone is employed upon a drawing tank the surface of the glass from which the draw is to occur is located a considerable distance below the roof or top stone, and a result the cooling of the glass in the Adrawing ring is relatively slow and a considerable loss of time occurs, due to the slow cooling of the glass. It will be seen that with our apparat-us this dilic-ulty is remedied by getting?T the upper edge 4 of the wall of the drawing extension as close as possible to the surface of the glass, so that such surface is better exposed to the cooling action of the air. Under these conditions the glass in the drawing rings in the extension cools much more rapidly than is the case where a perforate roof or top stone is employed. The speed of operation is also greatly increased bythe use of the movable drawing rings which are successively brought into position in the drawing extension. This is due to the fact that the Cold glass which is left in a ring after the drawing operation need not be reheated 0r refined in the extension, but can be immediately pushed out into the melting tank and a new ring filled with fresh glass brought from the melting tank into the extension, so that no time need be wasted due to any reheating operation intermediate the draws, as is the case where a fixed drawing ring is employed in connection with a top stone.

It will be seen that the bringing of the surface of the glass in the extension closer to the top surface of the walls thereof is made possible by the use of the cover 6 with the depending walls, such cover providing the heating chamber or heating space required over the surface of the glass. When the cover 6 is in the position indicated in Fig. 1 its interior registers with the passageway 9, and the surface of the glass in the extension 2 is exposed to a heat approximating that in the melting' chamber. The gate 10 serves to shield thf cylinder being drawn, from the heat suppiied through the passageway 9 (Fig. Uther advantages incident to the sinizilicity .if the structure and its ease of operation will be readily apparent to those skilled in the art.

What we claim is:

ln combination, a glass melting tank with its main portion roofed over and having a roofless extension at one side with side walls terminating adjacent the surface of the glass, an upright wall between the main portion of the tank and the extension, terminating above the level of the glass, and a drawingT shell circular in cross section and open at the top floating partially submerged `in the glass and adapted to be moved in such partially submerged position from the main portion of the tank beneath the said upright wall and into the said extension, the. said shell containing a body of glass in free communication with the glass in which the shell floats and having substantially the same exterior diameter as that of the interior of the extension, so that when in drawing position the shell substantially fills the extension.

ln testimony whereof we have hereunto signed our names in the presence of the sub scribed witnesses.

WILLIAM L. CLAUSE, ROGERS. PEASE.

Witnesses:

L. A. BAILEY, 

